The original 1928 publication by Thomas S. Stevens[2] concerned the reaction of 1-phenyl-2-(N,N-dimethylamino)ethanone with benzyl bromide to the ammonium salt followed by the rearrangement reaction with sodium hydroxide in water to the rearranged amine.
Stevens rearrangement 1928
A 1932 publication[3] described the corresponding sulfur reaction.
The reaction mechanism of the Stevens rearrangement is one of the most controversial reaction mechanisms in organic chemistry.[4] Key in the reaction mechanism[5][6] for the Stevens rearrangement (explained for the nitrogen reaction) is the formation of an ylide after deprotonation of the ammonium salt by a strong base. Deprotonation is aided by electron-withdrawing properties of substituent R. Several reaction modes exist for the actual rearrangement reaction.
In an alternative reaction mechanism the N–C bond of the leaving group is homolytically cleaved to form a di-radical pair (3a). In order to explain the observed retention of configuration, the presence of a solvent cage is invoked. Another possibility is the formation of a cation-anion pair (3b), also in a solvent cage.
In one application a double-Stevens rearrangement expands a cyclophane ring.[7] The ylide is prepared in situ by reaction of the diazo compound ethyl diazomalonate with a sulfide catalyzed by dirhodium tetraacetate in refluxingxylene.
^Stevens, T.S.; et al. (1932). "8. Degradation of quaternary ammonium salts. Part V. Molecular rearrangement in related sulphur compounds". J. Chem. Soc.: 69. doi:10.1039/JR9320000069.
^Bhakat, S (2011). "The controversial reaction mechanism of Stevens rearrangement: A review". J. Chem. Pharm. Res. 3 (1): 115–121.
^Strategic Applications of Named Reactions in Organic Synthesis Laszlo Kurti, Barbara Czako Academic Press (4 March, 2005) ISBN0-12-429785-4
^Macrocycle Ring Expansion by Double Stevens RearrangementKeisha K. Ellis-Holder, Brian P. Peppers, Andrei Yu. Kovalevsky, and Steven T. Diver Org. Lett.; 2006; 8(12) pp. 2511–2514; (Letter) doi:10.1021/ol060657a
^Tars K, Rumnieks J, Zeltins A, Kazaks A, Kotelovica S, Leonciks A, Sharipo J, Viksna A, Kuka J, Liepinsh E, Dambrova M (August 2010). "Crystal structure of human gamma-butyrobetaine hydroxylase". Biochem. Biophys. Res. Commun. 398 (4): 634–9. doi:10.1016/j.bbrc.2010.06.121. PMID20599753.
^Henry L, Leung IKH, Claridge TDW, Schofield CJ (August 2012). "γ-Butyrobetaine hydroxylase catalyses a Stevens type rearrangement". Bioorg. Med. Chem. Lett. 22 (15): 4975–4978. doi:10.1016/j.bmcl.2012.06.024. PMID22765904.
